Monday, May 4, 2009

Lately, Californians have been finding hundreds of dead Brandt's cormorants washed up on beaches near San Francisco. Most of the dead cormorants are notably emaciated, and wildlife officials suspect that a dip in the birds' food supply could be what is killing them. Specifically, biologists point to a decrease in the availability of anchovies, a staple of the Brandt's Cormorant's diet:

Last year, some species of small fish were scarce, according to trawl information gathered by the National Marine Fisheries Service. Northern anchovies - popular food for Brandt's cormorants - hit their lowest numbers since 1990 as the bulk of the fish moved to Southern California, where they normally spawn in years of cooler waters.

Steve Ralston, research fisheries biologist at the National Oceanic and Atmospheric Administration's Southwest Fisheries Science Center in Santa Cruz, said it took 10 trawls to catch one anchovy last year. In a typical year, more than 600 anchovies are caught in a trawl, he said.1

The fact that these seabirds are dying, likely as a result of our changing oceans, is just one example of the interconnectivity of life on our planet. Sadly, I think that we will continue to see more and more stories such as this one as our ocean ecosystem is affected by climate change and acidification, human use, and other impacts.